New memebr, first day with M37, questions

I just bought a 1954 M37 from a missouri surplus lot, brought it home, installed a new battery, and it fired right up and ran like a top. However, when the gas that was left in the tank ran out and I refilled it with some mower gas it began to run rough. Now I can hardly keep it running. It has a stock carb, motor, 12 volt electricals, and an electric fuel pump. Any ideas to help out a newbie?

Is your mower gas mixed with oil to help the lawn mower run or is it straight gas?

Prolly pulled a buch of crap into the filters. Swap them out. Have you inspected the tank to see how much crap is in there?

mower gas is realitivly new straight gas, i found one filter under the carb and cleaned it out, but no improvement. I have not inspected the tank yet. The vehicle is a former fire truck, and sat for about 6 mos. before i bought it. Are there other filters I should be looking for?

Maybe some of the crud plugged the fuel pickup? Can you run some pressurized air from the feed back to the tank? I don't have any past with M37s just going off your description.

How much gas is in the tank? If its just a couple gal. I would drop the tank and inspect.

most of the time there is another fuel filter under the drivers side seat around the frame. trace the fuel line back up and see. that one gets all the trash before it hits the tank. check it out an post back Tim

Thanks, I will check the tank tomorrow I should have done that first, but I was so excited that the thing fired right up, that I forgot. I will also trace the fuel lines and look for additional filters(maybe one near the electric fuel pump)..If that doesn't work I guess Ill tear into the carb.

Thanks for your insight, my M37 project is only one day old, so you will probably be hearing again in the near future..

Chris

The earliest M37 trucks had a large fuel filter with cleanable brass element attached to the bracket holding the voltage regulator. Later trucks had an in-tank fuel filter.

However, since the truck has been converted to 12 volt and an electric fuel pump added - other changes in the fuel system are anyone's guess.

Hope this helps,
David

Sorry, but somebody had to do it.....

My brain can picture this whole operation without giant picture files.. Put a spare gas can into the bracket on your RF side and run a fuel hose to the input side of the electric fuel pump ... whack the side of the carb a couple times with a hammer and away you go...Then you can rip out all the crudded up stuff in the system and still drive the truck... Is the OEM combination pump still hooked up or gone? Remember that it is a booster for your windshield wipers too...

Update: There is no fuel filter anywhere from the tank to the carb. i took apart the fittings at the fuel pump(mounted near rear axel), and had plenty of fuel. I have a pressure regulator near the carb, took that apart, no crud, and again plenty of fuel. when i take the small bolt out of the bowl on the underside of the carb it dumps quite a bit of fuel, no crud. my next move is to take apart the carb and see if something is in there. I also added more fuel to the tank in hopes that the original fuel that I added was watery, no improvement. I can only get the truck to run very rough for only a few seconds at a time. If I press the gas it dies..

Sounds like a blown accelerator pump. Check the status of your accelerator pump and report back.

I was thinking the same thing !!

I didn't have alot of time to spend on the beast today, I checked and blew out the fuel system from the tank to the carb, installed a new fuel regulator., imediatly after I put the new regulator in, she started and ran like a champ for about 5 minutes. Then she died and went back to not wanting to run. I exchanged the regulator for a new one, (and installed a fuel filter), but still couldn't get any results. Does that fit in your theory about the accelorator pump? I made a call to a friend of mine who builds dragsters in his free time, he is going to come over and help me out with the carb in the next few days. (he's better at that sort of thing than I am)

I've been looking for an M37 for about a year now, this one will soon be dressed back in OD, is there any way to find out where it was originally?

thanks for all the help

chris

A picture of your new ride would be nice for those of us who like to look at such things....

As for the history of your truck you can take some 400 grit sand paper and on the left and right ends of the front bumper start sanding lightly taking a layer of paint off at a time. (this is time consuming so plan accordingly) As you take the layers of paint off look for letters and numbers (that is if your truck wasn't sandblasted at some point) these are the bumper markings and may give you an idea into the life of the truck.

For example on the left hand side as your look at the truck you should get something like 1I 23E and on the right hand side you should get something like C-35. Then it is just a matter of figuring out the code. In my example I made the truck in the 1st Infrantry Division, 23thrd Engineers, Company C (Charlie) and vehicle #35 in the order of march or movement. Once you get the numbers you can post them here and someone should be able to help you figure the code out.

Also do the same on your hood to get the registration number. It should be on the middle side of the hood give or take.

You may also want to check the ignition system. It may work fine when cold, but hot spark may be weak. Check coil and condenser

I didn't think the M37 Carb has an accelerator pump.

Thanks for the advice on the bumber numbers, I can just make out US Army and some numbers on the tailgate, I'll investigate further this weekend.

I bought the truck for the GSA lot in Lebanon Missouri, I transported it to Columbia on a roll-back truck on Friday. I put a battery in it and it fired right up. I took it around the block, and ran it through all the gears with no problems. The guy at the surplus lot said it had been there for about 6 mos, and spent the last few years as a Brush Truck for the Conway Rural Fire District. It has the original motor, tranny, etc. It has an after-market electric fuel pump and is now 12 volts. The top is shot, as is the seat covering and tires, but only has a little surface rust in the bed. I paid 2100.00 for it, not knowing if it ran or not. I went down and looked at it last month. At that time they also had a couple of Kaisers and a 1950s M38 on the lot.

My buddy is coming over this weekend to pull the carb for me and give the truck a good once over. He thinks I pulled some grit into the carb, and it should be an easy fix..

Chris

I forgot to say that it has 3140 miles on it.